Need help/advice - Psychological ED (can’t maintain) - Fast heartbeat

Previously used porn every day and used death grip for 2 years. Also was taking finasteride until march of this year.

Stumbled into a relationship around February and only really committed to fixing my ED about 4 weeks ago. (Gym, no porn, masturbate once a week w lube) She is aware of my issues lol.

We finally were able to have sex this last weekend and I thought I made a breakthrough and got my confidence back. The following 2 days I would get random erections just thinking about her and doing it again.

Then last night we tried again, and I was unable to maintain long enough for penetration.

I get hard almost every time we make out and cuddle, but I really struggle to maintain the erection for long enough for penetration. When I try, my heart begins to beat really really fast and I start sweating as well. I’ve also tried using Viagra a few of the times and it doesn’t really help.

Do I just need to go to therapy to fix the psychological ED or am I improving and just need time?